Share Email Print

Proceedings Paper

Optimization of source distribution for half-wavelength DOE
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

A lot of source shapes have been proposed for resolution enhancement in semiconductor exposure field, and so-called OAI (OAI: Off Axis Illumination) in them improves not only the resolution but also defocus behavior. Such kind of small window illumination was realized aperture filter at first stage but there were issues of efficiency of light source and complex OPC due to higher coherency. The advantages of use DOE (DOE : Diffractive Optical Element ) are not only the flexible illumination shape available but also the controllability of intensity profile in addition to the higher efficiency of light source. However DOE design and fabrication to obtain enough resolution are difficult due to the huge design load and leading-edge fabrication. Not enough design and fabrication error lead unintended intensity distribution, and the distribution degrades the resolution and makes OPC less effective so that photomask specification shall be tighter. In this paper, as one example, dipole source shape named "Soft-Dipole" is optimized considering intensity distribution targeting 90nm with simulator and is estimated the impact to resolution and OPC. Then actual DOE is fabricated for the intended distribution and evaluated the behavior with the simulator of the DOE using captured intensity distribution. The result showed Soft-Dipole illumination had possibilities to reduce OPC load with enough resolution. Then the DOE design, the fabrication and the evaluation are discussed in this paper.

Paper Details

Date Published: 20 May 2006
PDF: 12 pages
Proc. SPIE 6283, Photomask and Next-Generation Lithography Mask Technology XIII, 62832U (20 May 2006); doi: 10.1117/12.681810
Show Author Affiliations
Ryuji Horiguchi, Dai Nippon Printing Co., Ltd. (Japan)
Nobuhito Toyama, Dai Nippon Printing Co., Ltd. (Japan)
Kimio Itoh, Dai Nippon Printing Co., Ltd. (Japan)
Kouji Yoshida, Dai Nippon Printing Co., Ltd. (Japan)
Masaaki Kurihara, Dai Nippon Printing Co., Ltd. (Japan)

Published in SPIE Proceedings Vol. 6283:
Photomask and Next-Generation Lithography Mask Technology XIII
Morihisa Hoga, Editor(s)

© SPIE. Terms of Use
Back to Top